Measurement method for polarity-inverted layered piezoelectric thin films using scanning nonlinear dielectric microscopy

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K04725
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General applied physics
• Research Institution: National Institute of Technology, Kumamoto College
• Principal Investigator: ODAGAWA HIROYUKI 熊本高等専門学校, 地域イノベーションセンター(熊本キャンパス), 教授 (00250845)
• Co-Investigator(Kenkyū-buntansha): 柳谷 隆彦 早稲田大学, 理工学術院, 准教授 (10450652)
• Co-Investigator(Renkei-kenkyūsha): CHO YASUO 東北大学, 電気通信研究所, 教授 (40179966)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 分極反転 / 圧電薄膜 / 走査型非線形誘電率顕微法 / 極性反転構造

Outline of Final Research Achievements

Recently, it is reported that the polarity of ZnO and AlN piezoelectric thin film fabricated by radio frequency (RF) magnetron sputtering method can be switched by changing the growth condition, and polarity-inverted structure has been obtained. In this research, we have developed the quantitative measurement method for the thickness of a polarity inverted layer using canning nonlinear dielectric microscopy (SNDM). We derive an equation that represents the relationship between the output signal and the oscillation frequency of the SNDM probe, and developed the measurement procedure that can determine the thickness of polarity-inverted single layer structure. We applied it to two-dimensional distribution measurements of the layer thickness. Moreover, we investigated the measurement for double layered structure. We showed that it is possible to determine the thickness of two layers by controlling depth profile of electric field inside the measurement materials using a soft probe tip.

Free Research Field

圧電材料の評価技術、圧電デバイス